Experience of a bespoke hyperkalaemia clinic to facilitate prescribing of renin-angiotensin-aldosterone system inhibitors in patients with heart failure with reduced ejection fraction

BackgroundRenin-angiotensin-aldosterone system inhibitors (RAASi) improve prognosis in patients with heart failure with reduced ejection fraction (HFrEF), but suboptimal dosing or discontinuation of these medications often occurs due to RAASi-associated hyperkalaemia. We established a nephrology-led hyperkalaemia clinic to oversee prescribing of patiromer, an oral potassium-binder, to facilitate RAASi optimisation. MethodsThe clinic was established in July 2019 at a nephrology tertiary centre in the United Kingdom. Patients with HFrEF who were unable to increase RAASi dosage due to hyperkalaemia were referred to the clinic, where all patients commenced patiromer 8.4g daily. RAASi adjustments were deferred to the referring teams. Study outcomes included the percentage of patients who achieved a RAASi dose increase and the proportion of patients with normokalaemia at follow-up. Outcomes were evaluated until 1st May 2021. ResultsA total of 34 patients were reviewed in the clinic between July 2019 and December 2020. Mean age was 71.6 years (+/- 10.6 years), 56% had diabetes and 71% had chronic kidney disease stages 3a-5; mean estimated glomerular filtration rate was 56ml/min/1.73m2 (+/- 21ml/min/1.73m2). During follow-up, 12 patients discontinued patiromer (6 of whom did so due to gastrointestinal side effects) and were discharged; two patients died from non-hyperkalaemia related illness, and one switched to an alternative potassium-binder. Over a mean follow-up of 13.4 months (+/- 5.8 months), 17 of the 20 patients (85%) who continued with a potassium-binder achieved a RAASi dose increase, with 4 patients (21%) receiving maximal dosages. This was attained by achieving normokalaemia during follow-up. No patients required magnesium supplementation. Of the 19 patients on patiromer, 12 continued this therapy for more than 12 months and 4 received it safely for 20 months. Discussion/ConclusionPatiromer prescribing in a nephrology-led hyperkalaemia clinic facilitated RAASi up-titration in patients with HFrEF by controlling potassium levels.